Typical toilet plumbing has a lead (Pb) pipe which extends downwardly from the bowl of the toilet into the space between the floor supporting the toilet and the ceiling of the room beneath the toilet. The lead pipe curves in this space about 90.degree. for joining with a ferrule by a wiped solder joint. The ferrule is usually sealed to a TY section of a soil stack with a caulked lead (Pb) and oakum joint. Occasionally the lead (Pb) pipe may extend between the toilet and the ferrule without bending about 90.degree. as, for example, when a toilet is installed in a cellar and directly connected to a sewer beneath the cellar.
The soil stack and TY section are usually made from a thick cast iron. The ferrule is usually made from a thick brass. The pipe from the toilet to the ferrule, however, is often made from lead (Pb); this pipe, therefore, is often the portion of the plumbing for the toilet which first deteriorates and leaks.
Installing the lead (Pb) pipe for toilets in new construction has required both considerable effort and careful scheduling relative to completion of other portions of the structure to make the installation most easily. The oakum must first be packed between the ferrule and the TY section and then lead, heated to approximately 700.degree. F. (370.degree. C.), poured over the oakum between the ferrule and the TY section. Caulking of the cooled lead joint with special chisels then completes the seal between the ferrule and TY section. The other end of the ferrule has been previously fitted to the lead (Pb) pipe with a sealing bead of solder wiped about the fitted joint. The pipe usually curves upwardly from the joint through a floor built above the lead pipe for supporting the toilet. A flange is then secured to the end of the lead (Pb) pipe at the floor and the flange secured to the toilet. The flange may also be secured to the floor with fasteners.
The ceiling of a room beneath the toilet may then be installed. The ceiling cannot be installed until the plumbing for the toilet has been completed because the limited space between the floor which supports the toilet and the ceiling of the room beneath the toilet usually does not provide enough space for making the caulked lead (Pb) and oakum joint used in installing the toilet. Thus, even in new construction, installing a toilet has required both difficult-to-make caulked oakum and lead (Pb) and solder joints as well as scheduling of the construction to first complete the plumbing for the toilet and then finish the floor which supports the toilet and the ceiling of the room below the toilet.
When the pipe from a toilet springs a leak, it must, of course, be replaced. Replacing a lead (Pb) pipe, like initially installing the lead (Pb) pipe, has been a difficult operation. The toilet must first be removed from the flange on the pipe. A hole is then cut in the floor which supported the toilet to provide access to the leaking pipe. The leaking lead (Pb) pipe is then cut off, usually with a reciprocating saw. The caulked oakum and lead joint must also be removed, a process which usually requires that the ferrule be removed with a hammer and chisel. If the hammering and chiseling damages the TY section of the soil stack which, usually being cast iron, can crack and cannot be repaired, a major reconstruction job of replacing the TY section of the soil stack becomes necessary.
Even if the old ferrule is successfully removed from the TY section of the soil stack without damage, a new ferrule must then be installed. Installing the new ferrule requires inserting a new oakum packing, pouring molten lead about the oakum, and then caulking the molten lead to again form a permanent seal between the ferrule and the TY section of the soil stack. The new lead (Pb) pipe must also be connected to the new ferrule with a wiped solder joint.
The limited space between the floor which supports the toilet and the ceiling of the room beneath the toilet usually prevents properly forming the caulked oakum and lead joint between the TY section of the soil stack and the ferrule without opening the ceiling of the room beneath the toilet as well as the floor which supports the toilet. Both the floor and ceiling must then be replaced thereby to make quite expensive the installation of the new lead (Pb) pipe. In addition, the old ferrule was probably in satisfactory condition (because of its heavy construction) even though the lead (Pb) pipe had sprung a leak. Replacing the old, but satisfactory ferrule with a new ferrule then wastefully requires supplying the new ferrule. Of course, proper tools, including equipment for heating the new molten lead (Pb) joint to approximately 700.degree. F. (370.degree. C.), are also needed.
Although it would seem that an easier way of replacing the leaking lead (Pb) pipe would be to separate the old pipe from the ferrule at the wiped solder joint between the two and then connecting a new lead (Pb) pipe to the old ferrule with a new wiped solder joint, the wiped solder joint cannot be formed satisfactorily while the ferrule is connected to the TY section of the soil stack. Even if a way of properly forming the solder joint between the pipe and ferrule while the ferrule is connected to the TY section of the soil stack were found, forming such a joint would still be likely to require removing the ceiling of the room beneath the toilet as well as the floor which suports the toilet to provide adequate room for forming the solder joint. The additional expense of replacing the ceiling as well as the floor will thus still be required.
In recent years polyvinyl chloride (hereinafter PVC) plumbing pipes have become available. Such PVC pipes, however, have not been available long enough to have been used in a significant portion of toilet installations in this country. In addition, after the recent introduction of PVC pipes, their use was resisted until the satisfactory performance of such pipes could be demonstrated and local building codes then changed to permit their use. PVC pipes are thus not likely to be found in even relatively recent structures and are even less likely to be found in structures which are old enough for a lead (Pb) pipe to have deteriorated sufficiently to leak. Most toilets are thus connected to a cast iron soil stack by a lead (Pb) pipe and brass ferrule as described above.
Another recent development are pipe couplings formed from an elastomer such as neoprene. These couplings are compressible sleeves which extend over facing ends of pipes. Ring clamps which extend about the portions of the sleeve overlapping each pipe are then tightened to compress the sleeve about the pipes and thereby seal the coupling between the ends of the pipes. It is known, for example, to use such couplings for underground waste pipes. Such couplings, however, have not heretofore been used for installing or replacing the discharge pipes from toilets.
Compressible sleeve couplings are necessarily flexible in order to be compressed about ends of pipes connected with the coupling. This flexibility permits the coupling to bend. The coupled pipes therefore must be otherwise supported. When the couplings are used with underground pipes, the ground supports the pipes. If, however, such couplings were used for plumbing, the pipes of the plumbing would have to be connected to the structure for support. Metal plumbing pipes require only limited connections to the structure for support as compared to the additional connections to the structure which would be required if flexible sleeve couplings connected the pipes. The additional expense of such additional connections would largely negate the saving in cost over conventional pipe couplings which could be obtained from the use of sleeve couplings.
The support for pipes which are joined by a flexible, compressible sleeve not only must be adequate to support the pipes when they are installed, but also adequate to keep the pipes from shifting or sagging over the years after they are installed. Keeping the pipes from moving is particularly important when one of the pipes joined by a sleeve is the discharge pipe from a toilet because movement of the discharge pipe relative to the toilet could cause a leak between the toilet and pipe which, because the toilet covers the discharge pipe, could not be detected until the leak had caused noticable damage to the structure about the toilet.
It is also sometimes desirable to connect one plumbing pipe to another intermediate ends of the other pipe. With metal plumbing pipes, such connections were usually made by cutting a section from the other pipe and inserting a Y or T-shaped coupling in place of the section removed from the pipe. These couplings have an extra fitting to which the end of the one pipe then connected. Such a connection thus effectively requires the installation of three pipes and a coupling to make two flow paths through the pipes.